I once played a game where I controlled the Western Hemisphere and blockaded the entire rest of the world (In Meiou with its more valuable trade goods and 2x number of provinces. Thanks to the privateer and blockade NI, I was able to make so much money off of blockades that I made thousands a month without minting) The coastal repair idea reduced micromanagement too.
That was a completely unique game though, outside of that, those two NIs are bloody useless. I think that Nation Bank is a waste of an idea slot but the +prestige from battles are absolutely worthless. Grand Army also doesn't have much place in my books unless you are a tiny rich nation. It saved my bacon in my 14-province Cherokee vs all of Europe game.
That was a completely unique game though, outside of that, those two NIs are bloody useless. I think that Nation Bank is a waste of an idea slot but the +prestige from battles are absolutely worthless. Grand Army also doesn't have much place in my books unless you are a tiny rich nation. It saved my bacon in my 14-province Cherokee vs all of Europe game.